I had a bad experience with the BVC coils in my nautilus. Was excited to try it, and bought one as soon as they were in stock at my local B&M. It vaped amazingly. Till it reached the end of its life span. I read these are made of a ceramic wicking material that breaks down, It has a mesh screen over the coil. A few times toward the end of its life span, I felt like I sucked in a tiny piece of something solid with my vape which was scary. Ignored that but a day later, brown ooze started seeping from the air control hole in the nautilus (It is a COMPLETELEY clear juice I had in the tank (baja blast from killerjuice, delicious!) and had never used a dark juice in this tank. Never ever had this happen before, and scared me off from the bvc. Not sure if anyone else has had a similar experience.
As far as the burning feeling, I had a few bad coils at first that caused the burnt taste/feeling from leads crossing. I watched Rip Trippers youtube vid on rebuilding the nautilus coil head (single coil rebuild). It is really easy, saves money, and a much better vape and have never experienced the burnt taste/feeling since rebuilding these coil heads.
Kristy